body {
    font: 12px Arial;
}
path {
    stroke: steelblue;
    stroke-width: 2;
    fill: none;
}

.axis path,
.axis line {
    fill: none;
    stroke: grey;
    stroke-width: 1;
    shape-rendering: crispEdges;
}
.axis .minor line {
    stroke: lightgrey;
    opacity: 0.7;
    stroke-dasharray: 2,2;
}
.tooltip {
    display: none;
    padding: 3px;
    position: absolute;
    background-color: rgba(192,192,192,0.8);
    height: 90px;
    width: 85px;
}

.area {
    fill: rgba(70, 130, 180, 0.1);
    stroke: steelblue;
    stroke-width: 1px;
}

.brush .extent {
    stroke: #fff;
    fill-opacity: .125;
    shape-rendering: crispEdges;
}